Subsurface well apparatus



Aug. 9, 1966 K. LEUTWYLER 3,264,994

SUBSURFACE WELL APPARATUS Filed July 22, 1963 5 Sheets-Sheet l Kurt Leutwyler,

20g, INVENTOR 20V BY.

ATTORNEYS 9, 1966 K. LEUTWYLER 3,264,994

SUBSURFACE WELL APPARATUS Filed July 22, 1963 5 Sheets-Sheet 2 i n w I l l- --1 I TRIGGERING l l DETECTION I STATICIZING POWER SIGNAL i AND BATTERY AND SOURCE I I RECEIViNG l AMPUFYWG CHARGE I l /r d E 212 L l8 l6 J ENERGIZER FIRST FII'S L J L DETECTOR COINCIDENCE SIGNAL POWER AMPLIFYING GATE STATICIZER CIRCUITS z a z 38 4O 42 SECOND DETECTOR Kur'r Leutwyler lNVENTOR.

ATTORNEYS Aug. 1966 K. LEUTWYLER 3,264,994

SUBSURFACE WELL APPARATUS Filed July 22, 1963 5 Sheets-Sheet 5 Fig. 7

HIGH VOLTAGE '8 SOURCE I r, 1 1 L J "I POWER 'NTEGRATOR aSTATlCIZER L-AMPLIFIER I CIRCUIT )4 J 68 1 f 1 66 7o 72 260 Fig. 8. l m T 2 2 ;z z a z z z z f s z s z L to Ignition Circuii T/so I04 F I g. 6

Kurt Leutwyler INVENTOR.

to MM 260 ATTORNEYS United States Patent 3,264,994 SUBSURFACE WELL APPARATUS 7 Kurt Leutwyler, Whittier, Califl, assignor to Baker Oil The present invention relates to subsurface well appatus, and more particularly to an apparatus for the remote operation of oil well tools.

The basic concept of the invention is to provide an oil well tool with a self-contained powering source of potential energy which can be transformed into kinetic energy by the provision of a triggering signal or combination of signals at an extremely low level of energy. That is, a predetermined combination of physical phenomena, such as a supersonic signal or signals, a magnetic field, or a radioactive element will provide energy sufiicient to actuate a stored power source adequate to do the physical work involved in operating the particular tool. Through the use of modern, computer-type electronic circuitry, it is possible to transform such a low level impinging signal into an electrical signal of sufiicient magnitude and duration to operate electrical igniting or electro-mechanical releasing circuits. The working power system can be the energy stored in a compressed spring compresesd gas, hydrostatic pressure, or a gas generator such as a pyrotechnic type mechanical compound which rapidly generates gas. The actual tool operation may be accomplished by the release of the compressed spring, or a hydraulic or pneumatic actuating system built into the tools and which is operated by eX- panding gas or other fluid under pressure.

According to the present invention, an integral, annular power charge or propellant, preferably a chemical energy source, as well as means for igniting the stored power charge, are incorporated in the body of a down-hole tool, and also electrical circuitry, responsive to a low power, externally supplied triggering signal. Upon receipt of the proper triggering signal or signal combination, the normally quiescent electrical circuits are activated to provide an ignition current to the power charge, operating the down-hole tool.

The present invention, therefore, contemplates the incorporation of an electronic ignition package adjacent to the stored power charge, all in the down-hole device. The ignition package includes a detector-transducer which, in response to a signal, generates a low level electrical impulse. The term signal herein is intended to include all of the various forms of energy that can be transmitted and detected, including the electrical, magnetic, sonic and radiant forms thereof. A signal source, such as a permanent magnet, can induce an electrical signal in a suitable inductive transducer. By providing a pair of transducers, properly spaced, a travelling magnet can induce a pair of signals separated in time, which can be recognized by coincidence circuits.

Through the use of electronic computer-type circuits, the recognized signals can be amplified and staticized to the magnitude and duration necessary to provide electrical energy suflicient to ignite the stored power charge. Typically, an electrical ignition device, such as a resistance wire or a blasting cap, is employed to ignite the charge.

Conventional electronic computer-type circuits, such as and, or gates, one-shot multivi-brators, or other bilevel static storage devices, are easily combined to per- 'form the decoding and triggering tasks. Proximity detectors, such as inductive or capacitive pick-offs, or radiant energy detectors, which convert impinging energy into an electrical signal, permit a choice of many alternative systems according to the present invention.

In an embodiment of the invention, a down-hole tool has an annular cavity in which is placed a power charge or propellant ignitable by a bridge wire. An electronic system, including detection and ignition circuits and an electrical power supply, is also placed in the cavity adjacent to the stored power charge. Two inductive coils concentric with the annular cavity are axially spaced to provide separate electrical responses to the passage of a permanent magnet, which is adapted to either be lowered gravitationally, or pumped, down the well.

By proper spacing and winding of the coils, the magnet generates a signal in the first and then the second coil. The coincidence of a pulse in the first coil with a pulse of similar polarity in the second coil generates a signal which, when applied to staticizing and amplifying circuits, activates the ignition system to fire the power charge.

In another embodiment, the detector portion of the electronic system is a radiation-sensitive device, such as an ionization chamber, which is responsive to the emanations of a radioactive nuclear source which is transported through the well. When the source is in close proximity with the detector, the increasing of ionizing radiation over the background radiation is sulficient to activate the ignition system.

In a copending application of the present inventor, filed concurrently herewith, Serial No. 296,618, filed July 23, 1963, for Subsurface Well Apparatus, there is described and claimed a similar system in which appropriate sonic triggering signal-s are encoded and transmitted to corresponding decoding receivers in the downhole tool. Upon recognition of the proper code com bination, an electrical signal is generated, which is staticized and amplified to operate the ignition system.

Accordingly, it is an object of the present invention to provide a remotely actuated stored power charge which is incorporated in an oil well tool.

Another object of the present invention is to provide improved oil well apparatus with integral power charges and ignition circuits.

It is a further object of invention to provide an oil well tool with an integral power charge, electrical power supply, and normally quiescent electronic circuitry adapted to respond to a received triggering signal.

It is yet another object of invention to provide a downhole oil well tool which is energized by the reception of a determined signal combination.

It is still another object of the invention to provide a downhole oil well tool that can be operated by the passage of a passive triggering assembly.

A further object of invention is to provide a downhole oil well tool containing an integral power charge, internal electronic circuitry, and necessary electrical power supply operable in response to the receipt of predetermined, low energy triggering signals.

Still a further object of invention is to provide in a down-hole oil well tool an integral powering package responsive to externally supplied low power signals for actuating the tool.

It is yet another object of invention to provide in a down-hole oil well tool an integral power charge, a normally quiescent electronic circuit for firing said power charge, and receiving circuits response to low level magnetic signals for operating the tool.

It is still another object of the present invention to provide in a down-hole oil well tool an integral power charge and ignition package, including normally quiescent electronic circuitry, adapted to be activated upon receipt of a predetermined combination of low level magnetic signals.

A further object of the invention is to provide in a down-hole oil well tool an integral power package, including a power charge, electronic circuitry having a first, normally quiescent state, and a second active state and detecting apparatus reponsive to applied radiant energy for triggering the electronic circuits into the second state for Operating said tool.

It is yet a further object of invention to provide in a doiWn-hole oil well tool an integral power package, including a stored power charge, an electrical power supply, normally quiescent electronic circuitry having a second, active state for firing said power charge, and detection circuitry responsive to the passage of a permanent magnet to trigger said quiescent circuitry into said second state for operating the oil well tool.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from .a consideration of several forms in which it may be embodied. Such forms are shown in the drawings accompanying and forming part of the present specification. These forms will now be described in detail, illustrating the general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

Referring to the drawings:

FIGURE 1 is a longitudinal section of an apparatus embodying the invention disposed in .a well bore;

FIG. 2 is an enlarged longitudinal section of -a portion of a subsurface oil well device forming part of the apparatus disclosed in FIG. 1, prior to its actuation;

FIG. 3 is a view similar to FIG. 2 after actuation of the oil well device;

FIG. 4 is .a block diagram of the elements of the tool operating system according to the present invention;

FIG. 5 is a block diagram in somewhat greater detail of the electronic ignition package according to the present invention;

FIG. 6 is a partially block, partially schematic representation of an electronic triggering package operable in response to an applied magnetic field;

FIG. 7 is a block diagram of an alternative electronic triggering package adapted to be energized by a radioactive source;

- FIG. 8 is a block diagram of an alternative electronic triggering package adapted to be energized by a moving permanent magnet.

As disclosed in FIG. 1, a string of oil well casing A is disposed in a well bore and has a liner hanging apparatus B formed in its lower portion, which is adapted to support a liner C which can be lowered down through the well casing into a well bore below the casing by means of a suitable tubular string D extending to the top S of the well hate. The liner hanging apparatus B embodies its own source of energy for effecting its setting against the liner, initiation of the actuating mechanism being triggered from a suitable source, as for example, by lowering or pumping a suitable device E down through the tubular string from the top of the well bore.

' As disclosed most clearly in FIGS. 2 and 3, the liner hanger apparatus is of the general type disclosed in the application of Hiram H. Fisher, Ir., and William D. Myers, for Liner Hang-ing Apparatus, Serial No. 281,409, filed May 20, 1963. It includes a cylinder or housing 104 forming the lower portion of the casing string A extending to the top of the well bore and is capable of supporting the liner C therewithin that extends into the well bore below the hanger.

' The hanger apparatus further includes an elastic packing sleeve 116, made of mhber or rubber-like material, positioned between a pair of thrust rings 1118, 120. The thrust rings have tapered outer surfaces 118a engaging sets of split upper and lower extrusion preventing rings 200, 201 that are interconnected for joint lateral moveinent by providing a circular key 202 on one ring fitting within a companion circular groove 203 in the adjacent ring. The splits of each pair of rings are out of phase to avoid a straight-through longitudinal passage through them.

The bottom ring 201 of the lower pair engages a downwardly tapering surface 204 of the housing or casing collar member 104; whereas, the upper ring 200 of the upper pair engages an expander 126 slidable along the wall 104a of the housing or cylinder. The expander has an inner tapered surface 205 engageable with an external companion tapered surface 206 of a split slip sleeve or ring 128 adapted to move downwardly along the expander and inwardly into engagement with the periphery of a liner hanging member 209. A depending skirt portion 207 of a piston 208 engages the upper end of the split slip ring 128, this piston having an upper piston head 209a slidable along the inner Wall 104a of the cylinder 104 and located below the lower head 210 of a chamber 211 adapted to contain a power charge or propellant 212. The head 210 bears against .an upwardly facing shoulder 213 of the housing to prevent its downward movement, the upper end of the chamber being defined by an annular piston 214 slidable along the inner wall 215 of the cylinder 104 and secured to a protector sleeve 216 extending along the lower head 210 and the piston 208, and disposed initially across the entire liner hanging apparatus B to protect the same. The lower end of the sleeve 216 is located within a lower recess 217 in the housing, the sleeve being held in its initial position, covering the liner hanging members, by one or more shear screws or pins 218 securing it to the housing 104.

The annular piston head 214 carries a suitable side seal ring 21 9 adapted to slidably seal against the cylinder wall 215, leakage of fluid between the protective sleeve 216 and the lower chamber head 210 being prevented by an inner seal ring 220 on the head slidably seal ing against the periphery of the sleeve. Leakage of fluid between the piston head 209a and the cylinder wall 104a is prevented by a piston ring 221 slidably sealing against the latter; whereas, leakage of fluid between the protective sleeve 216 and piston head is prevented by an inner seal ring 222 on the latter slidably sealing against the periphery of the sleeve.

When the power charge or propellant 212 is ignited, as described hereinbelow, gas under an increasing pressure is generated in the annular chamber 211, acting upwardly on the annular piston 214. When the force on the piston 214 is sufiicient to overcome the shear strength of the lower screws 218, the latter are disrupted and the piston and its protector sleeve 216 moved upwardly in the housing or cylinder 104 to the extent limited by engagement of the piston with a stop member 230 at the upper end of the cylinder or housing 104; At this time, a by-pass groove or grooves 231 in the periphery of the sleeve 216 are disposed across the lower chamber head 210 (FIG. 3), allowing the gases to pass from the chamber 211 through the by-pass groove 231 into the annular cylinder space 232 formed between the protective sleeve 216 and the cylinder wall 104a, to exert a downward force on the piston 208.

When the protector sleeve piston 214 engages the stop member 230, the lower end 216a of the protector sleeve is disposed above the slip device 128, thereby removing the protector sleeve from its covering position relative to the inwardly movable elements of the liner hanger B. Return or downward movement of the protector sleeve 216 within the housing 104 is prevented by a suitable one-way ratchet or latch device mounted on the piston and engagaing the enclosing housing. As shown, a split sleeve 233 is mounted in a recess 234 in the piston 214 and has external teeth 235 thereon facing in a downward direction and adapted to engage companion internal ratchet teeth 236 in the housing 104 adjacent to and immediately below its stop member 230, such teeth facing in an upward direction. The ratchet sleeve 233 has cam teeth 237 adapted to coact with companion cam teeth 238 in the piston 214, so that any tendency for the piston to move downwardly will cause the downwardly tapering and coacting cam teeth 237, 238 to urge the sleeve 233 laterally outwardly to main its ratchet teeth 235 fully meshed with the housing ratchet teeth 236.

As the propellant or power charge 212 burns away, so as to generate the gaseous fluid at an increasing pressure, the piston 208 shifts downwardly in the annular cylinder space 232, forcing the slip sleeve 128 and expander 126 downwardly to shift the upper extrusion preventing members 200, 201 and the upper thrust ring 118 toward the lower thrust ring 120 and lower extrusion preventing members 200, 201, shortening the length of the packing sleeve 116 and contracting it laterally inwardly into engagement with the liner hanging member 209. Continued downward movement of the piston 208 shifts the slip sleeve 128 downwardly along the expander 126 and contracts it radially inwardly into anchoring engagement with the periphery of the liner hanging member 209, the slip sleeve having internal upwardly facing wickers or teeth 240 adapted to anchor themselves in the periphery of the liner hanging member. As the gas pressure increases, the packing sleeve 116 is shortened to a greater extent and is forced more firmly into engagement with the periphery of the liner hanging member. The development of sufiicient force will also shift the upper and lower sets of extrusion preventing rings 200, 201 into engagement with the liner hanging member 209, bridging the annular spaces between the upper expander 126 and liner hanging member, and between the lower portion 204 of the housing and liner hanging member, to preclude flow of the pliant, elastic packing material through such spaces. The exertion of an increasing downward force on the piston 208 by the gaseous fluid will wedge the slip sleeve 128 more firmly into engagement with the liner hanging member, insuring that the weight of the liner C will thereafter maintain the slip sleeve embedded in the hanging member, the downward force being transmitted through the expander 126, upper extrusion preventing rings 200, 201, and thrust ring 118 to the packing member 116, to maintain the latter effectively sealed against the periphery of the liner member 209.

The propellant or power charge 212 embodied in the annular chamber 211 between the protective sleeve 216 and the outer housing or cylinder 104 contains its own source of oxygen, and will gradually burn away to gen erate the required gaseous fluid under pressure for operating the apparatus B. Preferably, maximum pressure will be generated during a substantial period, which, for example, may be from about one-half second, after ignition of the propellant 212, to about ten to thirty seconds after ignition. Such relatively slow burning of the propellant is preferred, since its explosion, accompanied by its sudden release of energy, :might damage the parts of the apparatus.

Ignition of the propellant occurs as a result of heating a suitable ignition wire 260 (FIG. 5) embedded in the propellant, or within a readily ignitable match compound surrounding the ignition resistance wire and disposed in the propellant. Such ignition wire forms part of an electronic package mounted within the chamber 211 itself. An appropriate circuit is disposed in the chamber 211, which is responsive to a triggering signal for effecting completion of the circuit through the resistance igniter or bridge wire 260.

With reference now to FIG. 4, the tool operating power charge 212 and electronic ignition package 10 is represented as a single block, which is incorporated in the annular recess 21 of the down-hole, subsurface well tool B. A triggering signal source 12, adapted to energize the circuit of the package 10 is represented by a separate block. It will be understood that the particular type of signalling device selected is determined by the choice of signal de- 6 tection apparatus employed for incorporation in the subsurface well apparatus.

Assuming that the signal source 12 provides some unique and recognizable phenomenon to which the downhole tool B can respond, the integral power charge 212 and ignition package 10 can be roughly divided into two element, a first, power charge element 212 and a second, electrical element 16. The power charge element 212 is preferably a gas generator, such as a propellant, railway flare, or other combustible chemical composition combined with an oxidizer, that is substantially self-contained and complete. Such a power charge can be energized by electrical igniting means, such as a resistance bridge wire 260, or a cartridge adapted to be fired by the provision of an electrical current.

A storage battery 18 provides the electrical current necessary to ignite or fire the stored power charge element 212. The storage battery 18 also powers the electrical circuits, providing the necessary stand-by electrical energy to maintain the electronic circuits in a quiescent state, as well as the energy to operate them in response to a received energizing signal. The electrical element 16, in addition to the battery 18, includes a detection and receiving circuit 20 and staticizing and amplifying ignition circuits 22.

In operation, the predetermined signal combination is detected at the detecting and receiving circuit 20 which, in response thereto, generates an electrical signal impulse at a low power level which is then applied to the staticizing and amplifying circuits 22. These circuits hold and amplify the signal impulse and, through suitable circuitry, provide electrical current of electrical energy sufficient to ignite the power charge element 212, which then generates the requisite mechanical energy for actuating the downhole subsurface well too. A common reference potential source, represented by the conventional ground symbol 24 has also been shown.

Turning next to FIG. 5, there is shown a generalized block diagram of an electrical system corresponding to the electrical element 16 of FIG. 4, applicable to the present invention. It is understood, however, that detailed circuit diagrams are unnecessary and that those skilled in the art will be familiar with the specific manner of interconnecting these circuits.

A first detector 30 and a second detector 32, both powered by the battery 18, are provided to detect and decode the impinging signal. The first detector 30 responds to a first stimulus and the second detector 32 responds to a second stimulus, both of which must be present before the down-hole apparatus is actuated. The output of the first detector 30 is applied to a first amplifier 34 and similarly, the output of the second detector 32 is applied to a second amplifier 36'. If the signal stimuli are sufiioiently great, the detectors generate signals which do not need amplification, and, in such an event, the amplifiers 34 and 36 may be omitted.

The outputs of the amplifiers 34, 36 are applied to a coincidence gate 38, which may be any of the well known electronic circuits adapted to provide an output signal on the occurrence of signals at all of the input terminals. In the present example, two inputs are provided and an output signal is generated in response to the coincidence of input signals. The output of the coincidence or and gate 38 is applied to a signal staticizer 40, which may be a conventional one-shot or monostable multi-vibrator circuit, or a flip-flop or bistable multi-vibrator circuit, both well known in the fields of electronic computer circuits. Other bi-level, or two state, memory type elements may be used to staticize the transient output of the detectors.

A one-shot is a device which operates in a first, stable mode to produce a first, low-level signal, but which, on the application of a suitable triggering signal, switches to a second, unstable mode of operation to produce a second, high level signal for an adjustable limited period of time, after which it returns to the first, stable mode. In the second mode of operation, the high level signal output is sustained to be of greater duration and magnitude than the output of the detector circuits. This operating signal output of the signal staticizer 40 is applied to power amplifying circuits 42, which, through the use of suitable power amplifiers, provide electrical power to activate the stored power charge energizing device.

In operation, therefore, a triggering signal at an extremely low energy level can, through the use of intermediate electronic detecting, staticizing and amplifying circuits, energize the stored power charge 212 adequate to operate the subsurface well tool B, which may be rugged and complex.

In the embodiment illustrated in FIG. 6, a signal detector, which may be located in the chamber 2'11, is adapted to respond to the presence of a moving magnetic field. An induction coil 50, made up of several turns of wire, is wound into a helical solenoid and located in the annular space 211 coaxial of the tool B. As is well known, a permanent magnet moving through a helix induces an electric current in the coil, which is connected to an amplifier circuit 52. The output of the amplifier circuit 52 is applied to a staticizer 54, the output of which is applied to a second, power amplifier 56. The power amplifier 56 may be only a power transistor, the base of which is connected to the output of the staticizer 54, and the emitter and collector of which serially connect an igniting device, such as the bridge wire 260, to the source of electrical energy. The circuitry just described is all located in the space 211, which also contains the propellant 212.

It will, of course, be recognized that to be operable in the down-hole environment, the tool parts 216, 104 defining the annular space will be made of non-magnetic material. This is to enable the induction coil 50 to detect the change in the magnetic field induced by the passage of a permanent magnet.

In operation, the velocity of the magnet will determine the amplitude of the induced electrical signal in the induction coil 50. The signal is amplified to trigger the staticizer 54 to provide a relatively high level signal for a fixed time interval. The rstaticized output signal is adequate to turn on the power transistor in the power amplifier 56, which conducts current sufficient to energize the bridge wire 260 and ignite the power charge 212.

In FIG. 7, there is shown an alternative electronic package adapted to be responsive to the presence of a radioactive source and which is located in the space 211. In this embodiment, the down-hole tool may assume any shape and need not be a hollow cylinder concentric with the well casing. However, assuming the same tool as shown in FIG. 6, an annular ionization chamber 62 is disposed in the space 211 and is connected to a source of relatively high voltage 64. The ionization chamber 62 may be a gas-filled hollow ring with an internal grid electrode that is maintained at the relatively high electrical potential.

As ionizing radiation passes through the chamber, an electrical discharge takes place between the grid and the surrounding walls which are maintained at the common or ground potential. An integrator circuit 66 is connected to the chamber 62 and is adjusted so that its leakage rate approximately equals the charging rate resulting from background radiation. The output of the integrator circuit 60 is applied to an amplifier 68, the output of which is applied to a signal staticizer 70, which, as above, may be a one-shot. The triggering threshold of the one-shot is adjusted so that the amplified output of the integrator circuit is normally below the threshold in the environment of background radiation alone. The output of the staticizer 70 is applied to a power amplifying stage 72, which, in turn, is connected to the power charge igniting circuits, including the igniter 260. As in the prior forms of the invention, all portions of the radiation detector circuitry are located in the chamber 211.

A radioactive source brought into proximity with the ionization chamber 62 discharges with a greater frequency, causing the output of the integrator circuit 66 to rise in magnitude until the triggering threshold of the staticizer 70 is exceeded. The output of the staticizer 70 is then amplified to provide an electrical signal of sufiicient magnitude and duration to fire the power charge 212, thereby effecting setting of the tool B against the device 209. If the configuration of the down-hole tool does not provide a hollow cylinder or cavity 211, then the ionization chamber may be a conventional Geiger-Mueller tube or similar radiation detector.

In the form of device shown in FIG. 8, there is shown an embodiment that is triggered by a permanent magnet lowered into or pumped down the well. A permanent magnet 74 may be provided with upper and lower packing elements 76, 78 so that it can be pumped through the well or the tubing string D.

The tool itself is modified to permit the magnet to affect the inductive coil, best accomplished by the :provision of aluminum, austenitic steel, or other non-magnetic metallic inserts in the tool, which define the boundaries of the annular space 211. Thus, the parts 216, 104, and also the liner member 209, are made of non-magnetic metal.

A receiver-detector circuit, suitalble for activation by the moving permanent magnet 76, which is not subject to false triggering by the presence of stray magnetic fields, is illustrated here. Referring to FIG. 8, there is shown here a pair of induction coils, each of which may be identical to the helical induction coil 50 of FIG. 6. A first helix 84 and a second helix 86 are oppositely wound and disposed concentrically in the space 211, being spaced apart axially by a distance equal to the effective separation of the poles of the permanent magnet 74, which is used as a triggering signal source. Each helix 84, 86 is connected to a separate amplifier circuit 88, 90, the outputs of which are connected to a coincidence circuit 92.

The output of the coincidence circuit 92 is applied to a staticizer 94, the output of which is applied to a power amplifier stage 96. It will be noted that once the triggering signal is received and amplified, substantially all of the above-described embodiments utilize a similar combination of coincidence circuits feeding a signal staticizer, which in turn, drives the firing circuits through a power amplifier stage. It will be understood that all components of the electronic ignition package ShOIWgI in FIG. 8 are housed in the chamber 211 of the too In operation, the circuits are normally quiescent until the permanent magnet 74, with a fairly strong magnetic field associated therewith, is caused to move through the well tubing D at a fairly rapid rate of speed and through the non-magnetic liner member 209. The magnet 74 travels in the axial direction with respect to the two helices 84, 86. When either of the magnetic poles passes through the first helix 84, an electrical pulse is induced therein, which, for example, may be assumed to be initially positive and then negative. As this first pole approaches the second helix 86, the opposite pole approaches the first helix 84, and, because the helices are oppositely wound, the signals induced in each of the helices simultaneously undergo the same voltage excursions.

Stray magnetic fields, on the other hand, simultaneously induce only oppositely directed electrical signals through both helices. Therefiore, the passage of magnet 74 results in a sulbstantially identical voltage excursion in both helices 84, 86, no matter which magnetic pole precedes. The induced voltages, amplified in the respective amplifier circuits 88, 90, are applied to the coincidence circuit 92, which responds to the simultaneous occurrence of signals of identical polarity at its inputs. The

coincidence circuit 92 then provides a signal to the staticizer 94, the output of which, as described above, is sufiicient to drive the power iam plifier 96 into saturation, igniting the power charge 212.

In the operation of the apparatus illustrated in FIGS. 1 and 8, the liner hanger B, with its movable elements protected by the sleeve 216, has been disposed in the well bore as a result of lowering the casing A therewithin, which is usually cemented in place. The liner hanger apparatus B contains the package, disclosed in FIG. 8, in its cavity 211. The hole below the casing is then drilled and the liner C lowered in the Well bore on the tubular string D, until the liner is in its appropriate location with its upper hanging member 209 overlapping the casing and disposed within the apparatus B. The magnet device E is then pumped down through the tubing string D and into the hanging member 209, energizing the coils 84 and 86 and triggering the resistance wire 206 to effect ignition of the power charge 212.

Upon its ignition, the power charge burns away, generating gas under an increasing pressure, which will elevate and remove the protector sleeve 216 and shift the slip sleeve 128 and packing structure 116, 200, 201 inwardly into firm engagement with the periphery of the liner hanging member 209. Following full setting of the liner hanger against the member 209, the tubing string can be rotated, as to the right, to effect its disconnection from the liner hanging member 209. Such disconnection is facilitated by providing a left-hand threaded connection 270 between the lower end of the tubular string and the member 209, in a known manner.

I claim:

1. In subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of detecting means operable in response to an applied energy signal for providing an output signal; staticizing means connected to said detecting means and operable in response to said output signal to provide an operating signal of duration and magnitude greater than that of said output signal; and powering means, including a source of work energy for operating the apparatus, connected to said staticizing means and operable in response to said operating signal for applying work energy to the apparatus, whereby an applied energy signal triggers the apparatus into operation; wherein said detecting means include signal amplifying means connected between said detecting means and said staticizing means; said staticizing means include a monostable multi-vibrator circuit and further include signal amplifying means connected between said staticizing means and said powering means; and wherein said powering means include gas generating means and means responsive to said operating signals for energizing said gas generating means.

2. In subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of detecting means including an inductive coil operable in response to an applied magnetic field signal for providing an output signal; staticizing means connected to said detecting means and operable in response to said output signal to provide an operating signal having a magnitude and duration greater than that of said output signal; and powering means, including a source of work energy for operating the apparatus, connected to said staticizing means and operable in response to said operating signals for applying Work energy to the apparatus, whereby an applied magnetic field signal triggers the apparatus into operation.

3. Apparatus of claim 2; wherein said detecting means include signal amplifying means connected between said detecting means and said staticizing means; said staticizing means include a monostable multi-vibrator circuit and further include signal amplifying means connected between said staticizing means and said powering means;

and wherein said powering means include gas generating means and means responsive to said operating signals for initiating operation of said gas generating means.

4. In subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of detecting means including an inductive coil operable in response to an applied magnetic field signal for providing an output signal; staticizing means connected to said dey tecting means and operable in response to said output signal to provide an operating signal having a magnitude and duration greater than that of said output signal; and powering means connected to said staticizing means, including gas generating means for operating the apparatus, and means operable in response to said operating signal for initiating operation of said gas generating means to apply work energy to the apparatus, whereby an applied magnetic field signal triggers the apparatus into operation.

5. In subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of detecting means including an inductive coil concentric with the well bore and operable in response to an applied magnetic field signal for providing an output signal; means for applying a magnetic field to said detecting means including a permanent magnet adapted to be transported through the well bore for inducing an electrical signal in said inductive coil; staticizing means connected to said detecting means and operable in response to said output signal to provide an operating signal having a magnitude and duration greater than that of said output signal; and powering means, including a source of work energy for operating the apparatus, connected to said staticizing means and operable in response to said operating signals for applying work energy to the apparatus, whereby a magnetic field signal applied by the moving magnet triggers the apparatus into operation.

6. Apparatus of claim 5; wherein said staticizing means include a monostable multi-vibrator circuit and further include signal amplifying means connected between said staticizing means and said powering means; and wherein said powering means include gas generating means and means responsive to said operating signal for initiating operation of said gas generating means.

7. In subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of radiation detecting means operable in response to an applied radioactive energy signal for providing an output signal; staticizing means connected to said detecting means and operable in response to said output signal to provide an operating signal of duration and magnitude greater than that of said output signal; and powering means, including a source of work energy for operating the apparatus, connected to said staticizing means and operable in response to said operating signal for applying work energy to the apparatus, whereby an applied radioactive energy signal triggers the apparatus into operation.

8. The apparatus of claim 7; wherein said radiation detecting means include an ionization chamber operable in response to impinging radioactivity for conducting an electrical current, and further including integrating circuit means connected to said ionization chamber and operable to provide an output signal in response to more than a predetermined electrical current in a unit time interval.

9. The apparatus of claim 7; wherein said radiation detecting means include an ionization chamber operable in response to impinging radioactivity for conducting an electrical current, and further including integrating circuit means connected to said ionization chamber and operable to provide an output signal in response to more than a predetermined electrical current in a unit time interval, and amplifying means connected between said integrating circuit means and said staticizing means.

10. Apparatus of claim 7; wherein said staticizing means include a monostable multi-vibrator circuit and further include signal amplifying means connected between said staticizing means and said powering means, and wherein said powering means include gas generating means and means responsive to said operating signal for initiating operation of said gas generating means.

11. In subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of radiation detecting means operable in response to an applied radioactive energy signal for providing an output signal; staticizing means connected to said detecting means including a monostable multi-vibrator circuit operable in response to said output signal to provide an operating signal of duration and magnitude greater than that of said output signal; and powering means, including a source of work energy for operating the apparatus, connected to said staticizing means and operable in response to said operating signal for applying work energy to the apparatus, whereby an applied radioactive energy signal triggers the apparatus into operation.

12. In subsurface well apparatus adapted to be lowered in a well bore, means for operating the apparatus comprising the combination of radiation detecting means operable in response to an applied radioactive energy signal for providing an output signal; staticizing means connected to said detecting means and operable in response to said output signal to provide an operating signal of duration and magnitude greater than that of said output signal; and powering means connected to said staticizing means, including gas generating means adapted to provide work energy for operating the apparatus, and means operable in response to said operating signal for initiating operation of said gas generating means to apply work energy to the apparatus, whereby an applied radioactive energy signal triggers the apparatus into operation.

13. In subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of detecting means including first and second inductive coils independently operable in response to an applied magnetic field signal for providing first and second output signals respectively; staticizing means connected to said detecting means and operable in response to the coincident occurrence of said first and second output signals to provide an operating signal of duration and magnitude greater than that of either of said output signals; and powering means, including a source of work energy for operating the apparatus, connected to said staticizing means and operable in response to said operating signal for applying work energy to the apparatus, whereby a magnetic field signal applied simultaneously to said first and second coils triggers the apparatus into operation.

14. In subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of detecting means including first and second inductive coils independently operable in response to an applied magnetic field signal for providing first and second output signals respectively; staticizing means connected to said detecting means including a monostable multi-vibrator circuit operable in response to the coincident occurrence of said first and second output signals to provide an operating signal of duration and magnitude greater than that of either of said output signals; and powering means, including a source of work energy for operating the apparatus, connected to said staticizing means and operable in response to said operating signal for applying work energy to the apparatus, whereby a magnetic field signal applied simultaneously to said first and second coils triggers the apparatus into operation.

15. In subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of detecting means including first and second inductive coils independently operable in response to an applied magnetic field signal for providing first and second output signals, and means for amplifying said first and second output signals; coincidence gate means connected to said detecting means and operable in response to the simultaneous provision of amplified first and second output signals to provide a third output signal; staticizing means connected to said coincidence gate means including a monostable multi-vibrator circuit operable in response to said third output signal to provide an operating signal of duration and magnitude greater than that of said third output signal; and powering means including a source of work energy for operating the apparatus, connected to said staticizing means and operable in response to said operating signal for applying work energy to the apparatus, whereby a magnetic energy signal applied to both coils triggers the apparatus into operation.

16. In subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of detecting means including first and second inductive coils independently operable in response to an applied magnetic field signal for providing first and second output signals; coincidence gate means connected to said first and second coils and operable in response to the simultaneous provision of said first and second output signals to provide a third output signal; staticizing means connected to said coincidence gate means and operable in response to said third output signal to provide an operating signal of duration and magnitude greater than that of said third output signal; and powering means including a source of work energy for operating the apparatus connected to said staticizing means and operable in response to said operating signal for applying work energy to the apparatus, whereby a magnetic field signal applied simultaneously to said first and second coils triggers the apparatus into operation.

17. In subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of detecting means including first and second inductive coils independently operable in response to an applied magnetic energy signal for providing first and second output signals; staticizing means connected to said detecting means and operable in response to the coincident occurrence of said first and second output signals to provide an operating signal of duration and magnitude greater than that of said output signals; and powering means connected to said staticizing means, including gas generating means adapted to provide a source of work energy for operating the apparatus, and means operable in response to said operating signal for initiating operation of said gas generating means to apply work energy to the apparatus, whereby an applied magnetic field signal triggers the apparatus into operation.

18. In a subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of detecting means including first and second inductive coils independently operable in response to an applied magnetic field signal for providing first and second output signals respectively; means for applying a magnetic field signal, including a permanent magnet, adapted to be transported through the well bore for inducing an electrical signal in said inductive coils; staticizing means connected to said detecting means and operable in response to the coincident occurrence of said first and second output signals to provide an operating signal of duration and magnitude greater than that of either of said output signals; and powering means including a source of work energy for operating the apparatus connected to said staticizing means and operable in response to said operating signal for applying work energy to the apparatus, whereby the permanent magnet transported through the well bore triggers the apparatus into operation.

19. Apparatus of claim 18; wherein said first and second inductive coils are respectively counterwound to provide opposite polarity signals in response to a moving first magnetic pole; said coils being axially spaced by a distance equal to the eifective spacing of the magnetic poles of said permanent magnet; said staticizing means include coincidence gate means connected to said first and second inductive coils for producing a third output signal on the simultaneous occurrence of first and second output signals of similar polarity; said staticizing means further include a monostable multi-v-ibrator circuit and signal amplifying means connected between said staticizing means and said powering means; and wherein said powering means include a gas generating means and means responsive to said operating signal for initiating operation of said gas generating means.

20. In subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of detecting means including first and second inductive coils concentric with the well bore and independently operable in response to an applied magnetic field signal for providing first and second output signals respectively; staticizing mean-s connected to said detecting means, including a monostable multi-vibrator circuit, operable in response to the coincident occurrence of said first and secondoutput signals of similar polarity to provide an operating signal of duration and magnitude greater than that of either of said output signals; and powering means, including a source of work energy for operating the apparatus, connected to said staticizing means and operable in response to said operating signal for applying work energy to the apparatus, whereby magnetic field signals of opposite polarity applied simultaneously to said first and second coils triggers the apparatus into operation.

21. In subsurface well apparatus adapted to be lowered in a well bore, means incorporated in the apparatus for operating the apparatus comprising the combination of detecting means including first and second oppositely wound inductive coils independently operable in response to an applied first polarity magnetic field signal for providing first and second output signals, respectively, and operable in response to an applied second polarity magnetic field signal for providing second and first output signals, respectively; staticizing means connected to said detecting means and operable in response to the coincident occurrence of one of said first and second output signals in both coils to provide an operating signal of duration and magnitude greater than that of either of said output signals; and powering means, including a source of work energy for operating the apparatus, connected to said staticizing means and operable in response to said operating signal for applying work energy to the apparatus, whereby magnetic field signals of opposite polarity, respectively, applied simultaneously to said first and second coils trigger the apparatus into operation.

References (Iited by the Examiner UNITED STATES PATENTS 1,079,690 11/1913 Bowler et a1 1661 15 1,757,288 5/1930 Bleecker 102--70.2 2,017,451 10/1935 Wickersham 285 X 2,593,725 4/1952 Brown 285144 X 2,897,895 8/1959 Ortfioff 285-145 X 2,938,592 5/1960 Charske et a1. 181-.5 3,040,658 6/1962 Maltby 102--19.2 X 3,050,150 8/1962 Tixier 181--.5 3,090,640 5/1963 Otteman et a1. 285145 X 3,100,444 8/1963 Ballet al 10221.6

CHARLES E. OCONNELL, Primary Examiner.

D. H. BROWN, Assistant Examiner. 

2. IN SUBSURFACE WELL APPARATUS ADAPTED TO BE LOWERED IN A WELL BORE, MEANS INCORPORATED IN THE APPARATUS FOR OPERATING THE APPARATUS COMPRISING THE COMBINATION OF DETECTING MEANS INCLUDING AN INDUCTIVE COIL OPERABLE IN RESPONSIVE TO AN APPLIED MAGNETIC FIELD SIGNAL FOR PROVIDING AN OUTPUT SIDNAL; STATICIZING MEANS CONNECTED TO SAID DETECTING MEANS AND OPERABLE IN RESPONSE TO SAID OUTPUT SIGNAL TO PROVIDE AND OPERATING SIGNAL HAVING A MAGNITUDE AND DURATION GREATER THAN THAT OF SAID OUTPUT SIGNAL; AND POWERING MEANS, INCLUDING A SOURCE OF WORK ENERGY FOR OPERATING THE APPARATUS, CONNECTED TO SAID STATICIZING MEANS AND OPERABLE IN RESPONSE TO SAID OPERATING SIGNALS FOR APPLYING WORK ENERGY TO THE APPARATUS, WHEREBY AN APPLIED MAGNETIC FIELD SIGNAL TRIGGERS THE APPARATUS INTO OPERATION. 